Disposable surgical drape construction



"Dec. 9, 1969 0. R.' L. FRANKLIN 3,432,557

DISPOSABLE SURGICAL DRAPE CONSTRUCTION Filed April 12, 1967 'INVENTOR:DONALD R. L. FRANKLIN United States Patent f 3,482,567 DISPOSABLESURGICAL DRAPE CONSTRUCTION Donald R. L. Franklin, Short Hills, N.J.,assignor, by

mesne assignments, to American Hospital Supply Corporation, Evanston,Ill., a corporation of Illinois Filed Apr. 12, 1967, Ser. No. 630,244Int. Cl. A61f 13/00; A61l 15/00 US. Cl. 128-132 8 Claims ABSTRACT OF THEDISCLOSURE BACKGROUND OF THE INVENTION In recent years, surgical drapesformed primarily of a soft, unsized and porous paper, referred togenerally as a non-woven cellulosic material, have gone into widespreaduse as a substitute for the older and less satisfactory linen drapes.Paper drapes are generally considered far superior to linen drapesbecause of their disposability and because they are more effective inblocking the passage of bacteria when the drapes become moistened bybody fluids or other fluids during surgical or obstetrical use. See W.C. Beck, Justified Faith in Surgical Drapes A New and Safe Material forDraping, American Journal of Surgery, volume 105 page 560, April 1963.To prevent the passage of moisture through paper drapes, the paper istreated to make it moisture resistant without at the same time blockingthe pores which permit the passage of air therethrough.

It has been recognized that plastic alone, in the form of a thin plasticfilm, might be an ideal bacterial barrier but, for surgical use, aplastic drape has been found completely unsatisfactory because itprevents the normal homeostatic mechanism of sweat evaporation.Moreover, the plastic material tends to increase the production of sweatand cause a substantial increase in a patients skin temperature.

It is apparent that any paper drape for surgical or obstetrical useshould have pliability, foldability, and, in general, drapability,similar to conventional cloth or linen drapes. Such properties may beachieved in a paper drape by utilizing a relatively soft, looselymatted, unsized paper similar in many respects to the material commonlyused for paper toweling. Preferably, the drape is formed from multiplelayers of such paper to make its draping properties more akin to thoseof linen.

Unfortunately, in conventional paper making strength is sacrified inorder to achieve proper draping characteristics, and therefore, in orderto provide the necessary strength, it has been considered necessary toreinforce the paper product with a scrim composed of threads of cottonor some other suitable material extending at right angles through thepaper fabric of the drape. The provision of such a loosely wovenreinforcing scrim greatly increases the difficulty and expense ofmanufacture of paper drapes and, at least to some extent, offsets theadvantages of disposability of such drapes. However, prior to thepresent invention, the provision of a woven reinforcing scrim has beenconsidered an essential feature of commercial paper surgical drapes.

3,482,567 Patented Dec. 9, 1969 SUMMARY OF THE INVENTION One aspect ofthe invention lies in the discovery that an effective drape for surgicaland obstetrical use may be achieved by eliminating the woven scrim of aconventional paper drape and substituting therefor a perforate layer ofstrong but highly flexible plastic material. The resulting productconsists essentially of an inner layer of polyethylene or other suitableplastic material with outer layers of relatively soft paper disposed onopposite sides of the integral plastic scrim or inner layer. A selectedarrangement of relatively large openings or apertures are provided inthe plastic sheet, such apertures performing the dual functions of (1)permitting the passage of air through the integral scrim, and (2)permitting adhesive contact through such openings by paper layers onopposite sides of the scrim. The scrim is therefore effectively anchoredin place by reason of adhesive attachment between paper layers withinthe relatively large areas defined by the openings in the plastic innerlayer or scrim. While openings of various sizes, arrangements, andshapes may be provided in the integral plastic scrim, most desirablysuch openings exceed the area of the unperforated portion of the scrimand are arranged in a grid pattern to provide substantially equalresistance to pulling forces exerted at right angles along the plane ofthe laminated drape.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a fragmentary perspectiveview of a composite drape embodying the present invention, the layers ofthe drape being partially separated to reveal the construction thereof;

FIGURE 2 is a fragmentary plan view of the drape with the top layerremoved to show the arrangement of openings in the intermediate or scrimlayer;

FIGURE 3 is an enlarged sectional view taken along line 33 of FIGURE 2.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to the drawings, FIGURE 1illustrates a portion of a surgical drape generally designated by thenumeral 10. For purposes of describing this invention, it is to beunderstood that the term surgical as applied to drapes also includesdrapes intended for obstetrical use and, in general, any drapes intendedto cover or underlie a patient in an operating room.

Drape 10 comprises outer paper layers 11 and 12 and inner plastic layeror scrim 13. The use of the word scrim in this context suggests thefunction of layer 13 as an internal reinforcement and is thereforeconsidered appropriate even though in terms of structure layer 13differs considerably from the woven scrim heretofore used in papersurgical drapes. Furthermore, as will be brought out more clearlyhereinafter, a distinctive cooperative relationship exists between theouter paper layers 11 and 12 and the plastic scrim sandwichedtherebetween.

Outer layers 11 and 12 are formed of a cellulose fabric or paper of thetype conventionally used in the fabrication of paper surgical drapes.Such paper is relatively soft, unsized, and preferably treated bymethods well known in the art to resist penetration and disintegrationwhen exposed to water, body fluids, and other liquids. At the same time,such paper is porous and permits the passage of air therethrough,thereby giving the drape the necessary breathing characteristics foroperating room use.

Paper layers 11 and 12 should be of substantial thickness, preferablyhaving a combined thickness (including the inner layer 13) in the rangeof approximately .005 to .035 of an inch. Such a thickness is importantnot only from the standpoint of providing adequate protection as abacterial barrier in the surgical environment, but also to-give properdraping characteristics to the product. For such purposes, it isexpected that layers 11 and 12 may each consist of multiple paper layersadhesively joined together, and that layers 11 and 12 are therefore inthemselves composite layers.

Inner layer 13 is composed of a single sheet of a highly flexible orfoldable plastic material having high strength characteristics.Polyethylene has been found effective, although other plastic materialssuch as non-rigid copolymers of vinyl chloride, vinyl chloride G.R.S.rubber, rubber hydrochloride, or polypropylene may also be used. Thethickness of the plastic layer may be varied considerably, dependingupon the reinforcing strength desired. In general, a thickness withinthe plastic film range of approximately .0005 to .002 of an inch ispreferred.

It will be observed that layer 13 is provided with a multiplicity ofopenings 14, the area of such openings in the aggregate exceeding thesolid surface area of the inner layer. The solid or impervious surfacearea is between the openings 14 which are distributed over the totalarea of the layer 13. Preferably, the openings are arranged in a gridpattern so that intersecting zones of plastic material 15 and 16 extendat right angles with respect to each other between opposite edges of thedrape. Such an arrangement results in a plastic scrim construction whichprovides substantial and equal resistance to tearing forces applied tothe drape at right angles along the plane of that drape. While theopenings 14 illustrated in FIGURES 1 and 2 are generally rectangular inshape, it will be understood that other shapes may be utilized withoutappreciably reducing the reinforcing properties of the integral plasticscrim.

FIGURE 3 somewhat schematically illustrates the manner in which theplastic scrim and the paper layers are interlocked together to form astrong surgical drape. As shown in the drawing, the porous cellulosicouter layers 11 and 12 engage each other within openings 14 of plasticscrim 13. A suitable adhesive or cement, such as polyvinyl acetateemulsion, securely bonds the outer layers together within such openingsand, in so doing, firmly locks the plastic scrim against movementbetween the sandwiching paper layers. While adhesive attachment betweenthe planar surfaces of the scrim and the contiguous surfaces of theouter paper layers may also be provided, such a connection is notessential. Thus, where untreated polyethylene is used as the fabricatingmaterial for the integral plastic scrim, a securely laminated surgicaldrape is obtained despite the well-known resistance or incompatibilityof such polyethylene with conventional adhesives.

In view of the above, it is believed apparent that the structure of thepresent invention constitutes a highlyetfective disposable surgicaldrape which enjoys the advantages of current paper surgical drapeswithout the substantial manufacturing and cost disadvantages thereof.While a plastic film is utilized in the construction of drape 10, thelarge openings in such film results in a scrim construction whichprovides reinforcing strength and breath ing characteristics necessaryfor surgical use.

While in the foregoing I have disclosed an embodiment of the inventionin considerable detail, it will be understood by those skilled in theart that many of these details may be varied without departing from thespirit and scope of the invention.

I claim:

1. A disposable surgical drape having outer layers formed from softfoldable paper and a reinforcing layer of a plastic material in sheetform disposed between said paper layers, said reinforcing layer having amultiplicity of openings therethrough distributed over the surface areathereof, said openings being of sufiiciently large size to permitopposed portions of said paper layers to be in contact through saidopenings, and adhesive interconnection between said contacting paperportions within said openings providing a secure bond between said outerlayers and effectively locking said plastic layer in place.

2. The surgical drape of claim 1 in which said plastic material ispolyethylene.

3. The surgical drape of claim 1 in which the area of the openings ofsaid plastic layer exceeds the surface area of the plastic materialtherebetween.

4. The surgical drape of claim 1 in which said openings of said plasticlayer are arranged in a grid pattern.

5. A disposable surgical drape having outer layers formed from soft,foldable, wet-resistant paper and a reinforcing layer of a plasticmaterial in sheet form disposed between said paper layers, saidreinforcing layer having a multiplicity of openings therethroughdistributed over the surface area thereof with solid surface areasbetween said openings, the total area of said openings exceeding thesaid solid surface areas therebetween, said openings being ofsufficiently large size to permit opposed portions of said paper layersto be in contact through said openings, and adhesive interconnectionbetween said contacting paper portions within said openings providing asecure bond between said outer layers and effectively locking saidplastic layer in place.

6. The surgical drape of claim 5 in which said openings are arranged ingrid pattern.

7. The surgical drape of claim 5 in which the thickness of said plasticlayer is within the plastic film range of approximately .0005 to .002 ofan inch.

8. The surgical drape of claim 7 in which said plastic material ispolyethylene.

References Cited UNITED STATES PATENTS 2/1934 Glidden et al. 16l-771/1966 Byrne 128538

